Fire bar for electric water heaters



Nov. 11 1924. 1,514,857

R. H. MEOINNES FIRE BAR FOR ELECTRIC WATER HEATERS Filed July 27. 1923 may Patented Novrll, 1924.

UNITED STATES 1,514,857 PATENT OFFICE.

ROBERT H. MAOINNES, OF HAMILTON,ONTARIO, CANADA, ASSIGNOR TO I). MOORE COMPANY, LIMITED, OF HAMILTON, CANADA.

FIRE BAR FOB ELECTRIC WATER HEATERS.

Application filed July 27, 1923. Serial No. 854,178.

To all whom it may concern:

Be it known that ROBERT H. MAoINNns, a subject of the King of Great Britain, residing at Hamilton, in the county of Wentworth and Province of Ontario, Canada, has invented certain new and useful Imrovements in Fire Bars for Electric Water eaters, of which the following is a specification.

My invention relates to improvements in devices for electrically heating water for household and other purposes, and more particularly to the fire bar or resistance wire support, and consists essentially of a plurality of independent elements or refractory sections each having an annular flange extendin nearly around it, the end portions of each ange being upon a common plane, there being in the intervening space between said ends a wall disposed at right angles with said flange, the flanges on said refractory sections one with the other constituting parallel grooves for the support of the resistance wiring, when superimposed one upon the other.

The principal object of the invention is to provide means whereby the resistance wire may be wound upon a round fire bar in parallel relation, and transversely of the bar, and not helically or spirally. A helically or spirally wound resistance wire, if broken, tends to straighten itself from annular position and unwind the entire bar with the result of short circuiting by coming in contact with metallic parts of the heater, whereas transverse winding if broken tends merel to back up in'its grooves.

A urther object is to provide in a round fire bar novel means of winding the resistance wire so that a resistance wire can be used of greater length than those that are helically wound, thus affording greater heat in a given length of bar.

Another object is to provide a device of the class described which will be simple, efficient, durable, and inexpensive to manufacture.

These, together with other objects, may be attained by the construction, combination, andnrrangement of the parts as will be hereinafter more fully described, illustrated in the accompanying drawing, and pointed out in the claims hereunto appended.

Referring to the drawing:

Figure 1 is an elevation of the improved fire bar showing the water jacket and reflector of the heater in crosssection:

F1g'ure'2 is a perspective view of one of the refractory sections showing in detail the under side; and,

Figure 3 is a perspective view of one of the refractory sections showing in detail the top side thereof.

Similar reference characters refer to similar parts throughout the several views.

Constituting the water jacket of the heater is the outer shell 2 and the inner shell or reflector 3 which have sealed connection at their open ends by the provision of the base rin 4. To the base ring is secured the switc box 5 and through it are carried the lead wires 6 to the switch 7.

The fire bar of the heater is made up of the base refractory section 8 which is supported in the base ring 4, end section 9, and a plurality of intermediate sections 10. In these sections are formed centre holes 11 through which the stay bolt 12 is passed securing all the said sexztions together to form a unit and also serves to form the neutral electrical connection for the heater. Holes 13 are also formed in each section for carrying the return resistance which may be led thereto from any point along the fire bar through channels 14. I do not claim the above construction as it is well known in the art, but I claim the construction of the individual fire bar sections and the consequent winding of the resistance wire as is now about to be described.

With the exception of the base section 8, end section 9, each section is formed with a recessed surface on one side and a circular rib 18 on the opposite side, the exterior diameter of which conforms substantially to the diameter of the said recess. The ribs 18 fit into the recesses in the adjoining sections and in this manner the sections are retained against radial movement. The base section 8 is recessed to receive the rib 18 on the adjoining intermediate section 10, and the end section 9 is provided with a rib 18 to enter the recess in the adjoining intermediate section 10, but not recessed as-are the said intermediate and base section, nor is the base section provided with a rib.

The ribs 18 each have two female impressions 16 in opposed portions thereof, one-of which receives a male stopper 17 formed in the recessed portion of the adjoinin section. The engagement of these fema e impressions with the male stoppers prevent rotary movement of the sections.

It will be observed that each of the refractory sections is in the form of a disc, and with the exception of the base section 8, all are provided with an annular or circumferential flange 15 which is preferably rectangular in cross section. This flange runs parallel with the disc shaped section, and the flanges on all the sections run parallel each with the other, and transverse of the assembled fire bar. The flanges terminate with an intervening space between their ends which are upon a common plane transverse of the fire bar, and when the sections are superimposed one to the other said intervening spaces constitute together a longitudinal substantially continuous lug formed of separate lugs 19 each intermediate of the ends of the respective flanges, thus forming two parallel longitudinal grooves 20. The end parts of the flanges 15 are beveled so that the space between them and the lugs 19 is .greater nearer the peripheric surface of the section than at the inside.

The. resistancewire 21 is wound upon'the assembled fire bar by weavingit back and forth along the grooves 22 formed between the flanges l5, and intermediate of said grooves it occupies the grooves 20 on either side of the lug 19, as the case may be, in staggered relation, as shown, the lug 19 insulating one portion of the resistancewire from another.

I'Vhen the heater is wired for a flat rate current, a group of sections at one end of the fire bar may be reversed, as shown, in F igure'l, the lug 19 being then at the opposite side of the fire bar, as shown in dotted lines. When this change is observed, the male stopper 17 on the section adjoining those which are reversed occupies the female impression 16 in the adjoining section opposite to that which would otherwise be occupied by the same. The reversing of a portion of the fire bar is not new in the art and consequently an explanation of the wiring is unnecessary.

There has thus been produced a simple and eflicient device of the classdescribed and for the urpose specified.

arious changes may be made in the construction of the heater itself without departing from the spirit and scope of the invention, as what I claim as new is the construction of the individual refractory section and consequent winding or weaving of the resistance wire.

.What I claim and desire to secure by Letters Patent, is

-1 A support'of refractory insulation material for the resistance of an electric fire bar comprising a disc, a flange formed on the periphery of the disc parallel with a plane at right angles to its axis, the flange being terminated to provide a short intervening space between its ends, and a lug formed on the disc longitudinally of its axis in said space equidistant of the ends of said flange, said disc being ,adapted to have resistance Wire laid against a surface of said flange transverse of the axis of the disc and turned around one end of the flange in one direction adjacent said lu and awe from the opposite end of the ange in t e opposite direction. a a

2. A support of refractory insulation material for the resistance ofan electric fire bar comprising a disc, a peripheral-flange formed on the periphery of the disc paral lel with a plane at right angles to its axis, the flange being terminated to provide a short intervening space between its ends, the ends of said flange being radial with respect to the axis of the disc, and a lug formed on the disc longitudinally of its axis in said space equidistant of the ends of said flange, said disc being arranged to have resistance wire laid in the grooves formed by said flange and turned around the ends thereof in opposite directions against said lug.

'3. A support of refractory insulation material for the resistance of an electric fire bar comprising a series of discs, flanges,

formed on the periphery of each disc paral laid in the grooves formed by said flangesand turned around the ends site directions.

4. A support of refractory insulation material for the resistance of an electric fire bar comprising a series of axially alined discs each having a peripheral flange formed on the periphery of each disc parallel with a plane at right angles to its axis, the flange being terminated to provide a short intervening space between its ends, and a lu formed on each disc extending longitudinally in said space equidistant of the ends of said flange, said lu'gs being alined on the several discs, said discs beingarranged to have resistance wire .laid between a surface of each flange and a surface of a flange on an adjoining disc thereof in oppoand turned around one end of the flange on signature. 7

ROBERT H. MAoINNES; Witnesses H. G. Hmnmr, F. D. Eanw. 

